Abstract 1175P
Background
Neuroendocrine Neoplasia (NEN) are a group of rare tumors with different prognosis and response to therapy depending on the site of origin, morphology and ki67. Temozolomide (TEM) seems to be active in metastatic NEN but there are limited evidence above all in gastrointestinal (GI) NENs. In this paper we analyzed the “real-world” data on TEM alone or associated to capecitabine (CAPTEM) in patients (pts) with mNEN.
Methods
One hundred consecutive advanced NEN pts treated with TEM or CAPTEM between 2009 and 2019 were included. A pre-treatment Tumor growth rate (TGR0) was calculated. Overall survival (OS), Progression-free survival (PFS), tolerance, objective response (ORR) and disease control rate (DCR)were analyzed. A propensity score analysis and cox regression models were used.
Results
TEM–based therapy was administered to 95 pts. (Table). On whole group mPFS was 10.4 (95%CI:6.0-11.5) months (m). In multivariate analysis, an higher risk of progression was observed for NEC G3 pts (HR:2.70, 95%CI:1.25-5.84) and for a TGR0 ≥19.55 (HR:2.53, 95%CI:1.45-4.40). Median OS was 23.4 (95%CI: 17.0-29.0) m and it was similar comparing TEM and CAPTEM (23.9 vs. 20.5 m, p =0.585). In multivariate analysis, pts with TGR0 ≥19.55 had an higher risk of death (HR:2.18, 95%CI:1.16-4.11) than those with TGR0<19.55, as well as NEC G3 (HR: 2.42, 95%CI:1.04-5.59) compared with NET pts. No differences according the primitive site. On 86 pts evaluable for response, ORR was 44.1% with a DCR of 70.9%. Mild adverse events (grade I-II) included anemia, neutropenia and headache. Rare cases of grade 3 neutropenia and thrombocytopenia were recorded Table: 1175P
Pts' main characteristics
| Median age | 59 (26-85) years n° (%) |
| PS ECOG 0-2 | 95 (100.0) |
| Carcinoid syndrome | 12 (12.6) |
| NET G1,G2,G3 | 75 (78.9) |
| NEC G3 | 20 (21.1) |
| TEM alone | 70 (73.7) |
| CAPTEM | 25 (26.3) |
Conclusions
TEM-based regimens are associated with a high DCR and a relatively tolerable toxicity profile in mNENs. Also pts with NET G3 tumors have a benefit. This regimen warrants further exploration in a prospective clinical trial not only in pancreatic but also in Gl and lung NETs.
Legal entity responsible for the study
Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori, IRST, IRCCS.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.